Django admin: cannot render VectorField as readonly

[Hornobster]

Django version 5.1.2
pgvector==0.3.5

When setting a VectorField in the readonly_fields property of a ModelAdmin or when the user does not have change permissions (just view permission), the template renderer crashes with:

The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

[ankane]

Hi @Hornobster, can you paste the full stack trace? (with any personal info removed)

[Hornobster]

Sure, here's the whole traceback from stdout:

Traceback (most recent call last):
  File "/django-root/.venv/lib/python3.12/site-packages/asgiref/sync.py", line 518, in thread_handler
    raise exc_info[1]
  File "/django-root/.venv/lib/python3.12/site-packages/django/core/handlers/exception.py", line 42, in inner
    response = await get_response(request)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/asgiref/sync.py", line 518, in thread_handler
    raise exc_info[1]
  File "/django-root/.venv/lib/python3.12/site-packages/django/core/handlers/base.py", line 284, in _get_response_async
    response = await sync_to_async(
               ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/asgiref/sync.py", line 468, in __call__
    ret = await asyncio.shield(exec_coro)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/asgiref/current_thread_executor.py", line 40, in run
    result = self.fn(*self.args, **self.kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/asgiref/sync.py", line 522, in thread_handler
    return func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/response.py", line 114, in render
    self.content = self.rendered_content
                   ^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/response.py", line 92, in rendered_content
    return template.render(context, self._request)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/backends/django.py", line 107, in render
    return self.template.render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 171, in render
    return self._render(context)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 163, in _render
    return self.nodelist.render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1008, in render
    return SafeString("".join([node.render_annotated(context) for node in self]))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/loader_tags.py", line 159, in render
    return compiled_parent._render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 163, in _render
    return self.nodelist.render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1008, in render
    return SafeString("".join([node.render_annotated(context) for node in self]))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/loader_tags.py", line 159, in render
    return compiled_parent._render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 163, in _render
    return self.nodelist.render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1008, in render
    return SafeString("".join([node.render_annotated(context) for node in self]))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/loader_tags.py", line 65, in render
    result = block.nodelist.render(context)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1008, in render
    return SafeString("".join([node.render_annotated(context) for node in self]))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/loader_tags.py", line 65, in render
    result = block.nodelist.render(context)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1008, in render
    return SafeString("".join([node.render_annotated(context) for node in self]))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/defaulttags.py", line 243, in render
    nodelist.append(node.render_annotated(context))
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/loader_tags.py", line 210, in render
    return template.render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 173, in render
    return self._render(context)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 163, in _render
    return self.nodelist.render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1008, in render
    return SafeString("".join([node.render_annotated(context) for node in self]))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/defaulttags.py", line 550, in render
    return self.nodelist.render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1008, in render
    return SafeString("".join([node.render_annotated(context) for node in self]))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/defaulttags.py", line 243, in render
    nodelist.append(node.render_annotated(context))
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/defaulttags.py", line 243, in render
    nodelist.append(node.render_annotated(context))
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/defaulttags.py", line 327, in render
    return nodelist.render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1008, in render
    return SafeString("".join([node.render_annotated(context) for node in self]))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/defaulttags.py", line 327, in render
    return nodelist.render(context)
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1008, in render
    return SafeString("".join([node.render_annotated(context) for node in self]))
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 969, in render_annotated
    return self.render(context)
           ^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 1067, in render
    output = self.filter_expression.resolve(context)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 718, in resolve
    obj = self.var.resolve(context)
          ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 850, in resolve
    value = self._resolve_lookup(context)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/template/base.py", line 917, in _resolve_lookup
    current = current()
              ^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/contrib/admin/helpers.py", line 302, in contents
    result_repr = display_for_field(value, f, self.empty_value_display)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/django-root/.venv/lib/python3.12/site-packages/django/contrib/admin/utils.py", line 445, in display_for_field
    elif value in field.empty_values:
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()
[2024-10-30 08:47:46,982]|ERROR| HTTP GET /admin/BSCore/alert/3bbb6539-2173-4c16-8796-0d6a6d4643dd/change/ 500 [0.47, 127.0.0.1:53402]

[ankane]

Thanks. I don't really see a way to fix this without a breaking change (having vector columns return a Vector object instead of an nd.array), so will consider this for 0.4.0.

[janosroden]

Workaround example:

from django.contrib import admin
from django.utils.safestring import mark_safe

@admin.register(m.Embedding)
class EmbeddingAdmin(admin.ModelAdmin):
    readonly_fields = [
        "vector_html",
    ]
    exclude = ["vector"]

    def vector_html(self, obj: m.Embedding):
        return mark_safe(f"""
            Length: {len(obj.vector)} <br/>
            <pre>{obj.vector}</pre>
        """)

    vector_html.short_description = "Vector"